WARREN,
he that is Security for Goods taken up on Credit, by extravagant young Gentlemen; also a Boarding-school, or a Bawdy-house, which are too much the same Thing.
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Entry taken from 1736 Canting Dictionary, by Nathan Bailey.
Warren in the 1811 Vulgar Tongue
Also see examples in Canting Songs and Slang Rhymes collected by John S. Farmer (1896).